Probability

Probability is about figuring out how likely something is to happen.

What it is: Probability is a number between 0 and 1 (or 0% to 100%) that tells you the chance of something happening. If something has a probability of 0, it will never happen. If it has a probability of 1, it will definitely happen.

Everyday examples:

• Flipping a coin: 50% chance of heads, 50% chance of tails
• Rolling a dice: Each number has a 1/6 chance (about 17%)
• Rain tomorrow: Weather says 30% chance of rain
• Getting a red card from a deck: 26 out of 52 cards are red, so 50% chance

How we use it: Probability helps us make decisions when we're not sure what will happen. Like:

• Should I bring an umbrella? (depends on chance of rain)
• Is this investment risky? (what's the probability of losing money?)
• Will my team win? (based on past performance and current conditions)

Simple ways to think about it:

• If you did the same thing 100 times, probability tells you roughly how many times each outcome would happen
• Higher probability = more likely to happen
• Lower probability = less likely to happen

Where it comes from: We calculate probability by looking at:

• How many ways something can happen
• How many total possible outcomes there are
• Past data (like how often it rained in March over the last 10 years)

Probability basically helps us deal with uncertainty by putting numbers on our best guesses about what might happen.